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| // Test the behavior of http://wg21.link/P0664, a proposal to catch any
// exceptions thrown after the initial suspend point of a coroutine by
// executing the handler specified by the promise type's 'unhandled_exception'
// member function.
//
// RUN: %clang_cc1 -std=c++14 -fcoroutines-ts \
// RUN: -triple=x86_64-unknown-linux-gnu -emit-llvm -o - %s \
// RUN: -fexceptions -fcxx-exceptions -disable-llvm-passes \
// RUN: | FileCheck %s
#include "Inputs/coroutine.h"
namespace coro = std::experimental::coroutines_v1;
struct throwing_awaitable {
bool await_ready() { return true; }
void await_suspend(coro::coroutine_handle<>) {}
void await_resume() { throw 42; }
};
struct throwing_task {
struct promise_type {
auto get_return_object() { return throwing_task{}; }
auto initial_suspend() { return throwing_awaitable{}; }
auto final_suspend() { return coro::suspend_never{}; }
void return_void() {}
void unhandled_exception() {}
};
};
// CHECK-LABEL: define void @_Z1fv()
throwing_task f() {
// A variable RESUMETHREW is used to keep track of whether the body
// of 'await_resume' threw an exception. Exceptions thrown in
// 'await_resume' are unwound to RESUMELPAD.
// CHECK: init.ready:
// CHECK-NEXT: store i1 true, i1* %[[RESUMETHREW:.+]], align 1
// CHECK-NEXT: invoke void @_ZN18throwing_awaitable12await_resumeEv
// CHECK-NEXT: to label %[[RESUMECONT:.+]] unwind label %[[RESUMELPAD:.+]]
// If 'await_resume' does not throw an exception, 'false' is stored in
// variable RESUMETHREW.
// CHECK: [[RESUMECONT]]:
// CHECK-NEXT: store i1 false, i1* %[[RESUMETHREW]]
// CHECK-NEXT: br label %[[RESUMETRYCONT:.+]]
// 'unhandled_exception' is called for the exception thrown in
// 'await_resume'. The variable RESUMETHREW is never set to false,
// and a jump is made to RESUMETRYCONT.
// CHECK: [[RESUMELPAD]]:
// CHECK: br label %[[RESUMECATCH:.+]]
// CHECK: [[RESUMECATCH]]:
// CHECK: invoke void @_ZN13throwing_task12promise_type19unhandled_exceptionEv
// CHECK-NEXT: to label %[[RESUMEENDCATCH:.+]] unwind label
// CHECK: [[RESUMEENDCATCH]]:
// CHECK-NEXT: invoke void @__cxa_end_catch()
// CHECK-NEXT: to label %[[RESUMEENDCATCHCONT:.+]] unwind label
// CHECK: [[RESUMEENDCATCHCONT]]:
// CHECK-NEXT: br label %[[RESUMETRYCONT]]
// The variable RESUMETHREW is loaded and if true, then 'await_resume'
// threw an exception and the coroutine body is skipped, and the final
// suspend is executed immediately. Otherwise, the coroutine body is
// executed, and then the final suspend.
// CHECK: [[RESUMETRYCONT]]:
// CHECK-NEXT: %[[RESUMETHREWLOAD:.+]] = load i1, i1* %[[RESUMETHREW]]
// CHECK-NEXT: br i1 %[[RESUMETHREWLOAD]], label %[[RESUMEDCONT:.+]], label %[[RESUMEDBODY:.+]]
// CHECK: [[RESUMEDBODY]]:
// CHECK: invoke void @_ZN13throwing_task12promise_type11return_voidEv
// CHECK-NEXT: to label %[[REDUMEDBODYCONT:.+]] unwind label
// CHECK: [[REDUMEDBODYCONT]]:
// CHECK-NEXT: br label %[[COROFINAL:.+]]
// CHECK: [[RESUMEDCONT]]:
// CHECK-NEXT: br label %[[COROFINAL]]
// CHECK: [[COROFINAL]]:
// CHECK-NEXT: invoke void @_ZN13throwing_task12promise_type13final_suspendEv
co_return;
}
struct noexcept_awaitable {
bool await_ready() { return true; }
void await_suspend(coro::coroutine_handle<>) {}
void await_resume() noexcept {}
};
struct noexcept_task {
struct promise_type {
auto get_return_object() { return noexcept_task{}; }
auto initial_suspend() { return noexcept_awaitable{}; }
auto final_suspend() { return coro::suspend_never{}; }
void return_void() {}
void unhandled_exception() {}
};
};
// CHECK-LABEL: define void @_Z1gv()
noexcept_task g() {
// If the await_resume function is marked as noexcept, none of the additional
// conditions that are present in f() above are added to the IR.
// This means that no i1 are stored before or after calling await_resume:
// CHECK: init.ready:
// CHECK-NEXT: call void @_ZN18noexcept_awaitable12await_resumeEv
// CHECK-NOT: store i1 false, i1*
co_return;
}
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